1. Free Fall and Projectile Motion
Unit 2
Free Fall and Projectile Motion

3. Ex. An object moves in ________________ with an
____________________ and an ____________________ .
(When graphing v vs. t, the area = _____________ .)
1 direction
initial velocity vi
acceleration a
distance vf
extra distance due
to acceleration B
dB = =
½ b h
½ t (vf – vi)
½ t (at)
½ at2 v vi A
distance if there is
no acceleration
dA =
L x W
= vi t t t

4. Total distance d: d = dA + dB
vit ½ at2
If an object is not accelerating, then ___________
In this case, the last equation becomes:
a = 0.
vit +
d =
½ 0t2
d = vit
This last equation is really the same as: v
= d/t
after it is solved for:
d = t v
since v is ______________ when a = 0,
then ______will be the same as _______.
constant v vi

5. are all in your _____________ . PhysRT NOT is _______ in PhysRT
One more equation:
vf2 = vi2 + 2ad
and these equations we studied before: v
= d/t
are all in your
_____________ .
a = Δv/t
PhysRT
vf = vi + at
but:
NOT
v = vi + vf 2
is _______ in PhysRT
All of these equations This is called:
only describe motion:  _____________________
kinematics

6. Physics Reference Tables, last page:
Which equation is not given?
v = vi + vf 2

7. In these equations, all of the quantities are
______________ . This means they have
_______________ and _______________ .
Ex: If a ball is thrown with an initial speed
of 7 m/s, use:
vi = ________ if is thrown upward/to right
vi = ________ if is thrown downward/to left.
Ex. If a rocket moves a distance of 35 m, use:
d = ________ if is moves upward/to right
d = ________ if is moves downward/to left.
vectors
magnitude
direction
7 m/s
-7 m/s
35 m
-35 m

8. Typical physics word problems involve objects
moving in ____ direction that: 1
…. and end at
another point with a __________
speed or velocity:
….begin at one
point with an
_________ speed
or velocity:
final
initial d vi vf
….and move a distance or displacement ____
with an average speed _____
and at an acceleration _____
during a time interval of _____ . d v a t

9. Use units to help you solve problems:
quantity
symbol
unit
abbrev.
of unit
time
distance or
displacement
speed or
velocity
acceleration
s or
sec
second t
meters d m
v, vi
vf, v
meters per
second
m/s
meters per
second squared a
m/s2

10. Word clues:
1. starts at rest  ______________
comes to rest  _______________
uniform motion  __________ , and
_____________________
4. constant velocity  _________________________
5. constant speed in 1 direction  ___________
Acceleration will always be ________________ .
It may be _________________, _________________
or _____ (still constant, but then _____________).
vi = 0
vf = 0
a = 0
vi = vf = v
see # 3 above
see # 3 above
constant
positive
negative
see # 3 above

11. 7. slows down: a and v are in _______________
directions
8. If an object collides with another object
(like Earth), then its final speed is _________ !
In this case, "final speed" means the speed
___________________________ it hits.
Whatever direction an object is moving is the
direction of its _____________________ .
10. If an object changes direction, then, at that
instant, only its ___________________________
MUST be zero.
opposite
NOT 0
the instant just before
velocity
speed and velocity